1. Field of the Invention
The present invention relates to a dual-band antenna and an antenna system, and more particularly, to a dual-band antenna and an antenna system capable of reducing interference.
2. Description of the Prior Art
As the wireless communication technology evolves, the demand for wireless networks increases. In the next generation, a standard of IEEE 802.11ac, exploiting multi-user multiple input multiple output (MU-MIMO) technology to enhance transmission rate, is widely adopted by the industry for communication products in wireless local area network (WLAN).
The operational frequency of wireless devices under the 802.11ac standard is mainly at 5 GHz. However, high frequency operation brings high scattering effect, which shortens a transmission range of the wireless devices. To achieve both high data rate and long transmission range, the wireless device under a WLAN, such as a wireless router, a wireless base station, a wireless access point, etc., may operate both at 2.4 GHz as well as 5 GHz. In another perspective, the wireless devices are usually equipped with multiple antennas. Some of the antennas may operate at both 2.4 GHz and 5 GHz, and some of the antennas may operate at 5 GHz. Due to the limited disposition space of the antennas, the antennas operating at both 2.4 GHz and 5 GHz would be easily interfered by the antennas operating at 5 GHz. Hence, it is necessary to improve the prior art.